Catalytic Staudinger/Aza-Wittig Sequence by in situ Phosphane Oxide Reduction
作者:Henri A. van Kalkeren、Colet te Grotenhuis、Frank S. Haasjes、C. Rianne A. Hommersom、Floris P. J. T. Rutjes、Floris L. van Delft
DOI:10.1002/ejoc.201300585
日期:2013.11
A Staudinger/aza-Wittig reaction sequence is described that is catalytic in phosphorus. Towards this end, the phosphaneoxide is reduced in situ by diphenylsilane, which allows for substoichiometric amounts of the catalyst 5-phenyldibenzophosphole to be used. The substrate scope is investigated and benzoxazoles, benzodiazepine imidates and a 2-methoxypyrrole were successfully synthesized. These investigations
Four- and five-co-ordinate complexes of heterocyclic tertiary phosphines with nickel(II), palladium(II), and platinum(II) dihalides
作者:David W. Allen、Frederick G. Mann、Ian T. Millar
DOI:10.1039/j39710003937
日期:——
The effects of variation in the steric and electronic properties of a number of heterocyclic unidentate tertiaryphosphine ligands on their ability to form five-co-ordinate tris(phosphine) complexes with nickel(II), palladium(II), and platinum(II) dihalides, have been studied.
Rapid intramolecular collapse of betaines derived from 5-phenyldibenzophospholes as compared with those derived from acyclic triarylphosphines; mechanism of the Wittig reaction in protic solvents
作者:David W. Allen、Barrie G. Hutley、Keith Polasik
DOI:10.1039/p19750000619
日期:——
rearranged phosphine oxides, the normal Wittig products being formed only to a small extent. These results are accommodated in a scheme in which rapid collapse of the initially formed cyclic, ring-strained, phospholium betaine (XI; R = H or OMe) occurs to form the normal Wittig products via the unstrained spiro-oxaphosphetan (XII; R = H or OMe). In the case of acyclic phosphonium betaines, collapse via the
5-苯基二苯并磷腈或其2,8-二甲氧基衍生物(VII; R = H或OMe)与氧化苯乙烯在乙醇中的反应仅产生正常的Wittig产物,苯乙烯和5-苯基二苯并磷腈5-氧化物(VIII; R = H或OMe)。相反,无环三芳基膦,三苯基膦和双-(对甲氧基苯基)苯基膦的相应反应主要产生重排的氧化膦,正常的维蒂希产物仅在很小的程度上形成。这些结果被包含在一个方案中,在该方案中,最初形成的环状,环应变的膦甜菜碱(XI; R = H或OMe)迅速崩解,通过未应变的螺-氧杂磷鎓(XII; R = H或OMe)。在无环phospho甜菜碱的情况下,崩溃通过氧杂磷鎓的合成不会如此迅速地发生,并且遵循了涉及甜菜碱的质子化和脱水以形成乙烯基phosph盐(IV)的替代途径。后者的水解主要产生重排的氧化膦(V)。
NEW POLYMER AND POLYMER LIGHT-EMITTING DEVICE USING THE SAME
申请人:Kobayashi Satoshi
公开号:US20080103278A1
公开(公告)日:2008-05-01
Provided is a polymer comprising a repeating unit represented by formula (1),
wherein, A
1
represents a divalent group in which the bond distance ratio (bond distance of C(α)-A
1
/bond distance of C(α)-C(β)) is 1.10 or more; R
1
, R
2
, R
3
, R
4
, R
5
, and R
6
, each independently represent a hydrogen atom, alkyl group, alkyloxy group, aryloxy group, arylalkyloxy group, etc. The polymer is useful as a light-emitting material, a charge transporting material, etc.